package com.xxx.blog.base.auth;

import com.google.gson.Gson;
import com.xxx.blog.base.config.ShiroConfig;
import com.xxx.blog.base.util.R;
import org.apache.commons.lang.StringUtils;
import org.apache.http.HttpStatus;
import org.apache.shiro.authc.AuthenticationException;
import org.apache.shiro.authc.AuthenticationToken;
import org.apache.shiro.web.filter.authc.AuthenticatingFilter;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;

import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/*******************************************************************************
 * Project: blog-base
 * Package: com.xxx.blog.base.auth
 * Type:    OAuth2Filter
 * Author:  ChenXuefei
 * Date:    2017/12/12 11:38
 *
 * Copyright (c) 2017 AFCATSTAR. All Rights Reserved.
 *******************************************************************************/
public class OAuth2Filter extends AuthenticatingFilter {
    
    @Override
    protected AuthenticationToken createToken(ServletRequest request, ServletResponse response) throws Exception {
        //获取请求token
        String token = getRequestToken((HttpServletRequest) request);
        
        if(StringUtils.isBlank(token)){
            return null;
        }
        
        return new OAuth2Token(token);
    }
    
    @Override
    protected boolean isAccessAllowed(ServletRequest request, ServletResponse response, Object mappedValue) {
        return false;
    }
    
    @Override
    protected boolean onAccessDenied(ServletRequest request, ServletResponse response) throws Exception {
        //获取请求token，如果token不存在，直接返回401
        String token = getRequestToken((HttpServletRequest) request);
        if(StringUtils.isBlank(token)){
            HttpServletResponse httpResponse = (HttpServletResponse) response;
            String json = new Gson().toJson(R.error(HttpStatus.SC_UNAUTHORIZED, "invalid token"));
            httpResponse.getWriter().print(json);
            
            return false;
        }
        
        return executeLogin(request, response);
    }
    
    @Override
    protected boolean onLoginFailure(AuthenticationToken token, AuthenticationException e, ServletRequest request, ServletResponse response) {
        HttpServletResponse httpResponse = (HttpServletResponse) response;
        httpResponse.setContentType("application/json;charset=utf-8");
        try {
            //处理登录失败的异常
            Throwable throwable = e.getCause() == null ? e : e.getCause();
            R r = R.error(HttpStatus.SC_UNAUTHORIZED, throwable.getMessage());
            
            String json = new Gson().toJson(r);
            httpResponse.getWriter().print(json);
        } catch (IOException e1) {
            
        }
        
        return false;
    }
    
    /**
     * 获取请求的token
     */
    private String getRequestToken(HttpServletRequest httpRequest){
        //从header中获取token
        String token = httpRequest.getHeader("token");
        
        //如果header中不存在token，则从参数中获取token
        if(StringUtils.isBlank(token)){
            token = httpRequest.getParameter("token");
        }
        
        return token;
    }
    
}
